U.S. application Ser. No. 599694, filed July 28, 1975 discloses inter alia that compounds of the formula (II): ##STR2## and their salts wherein X is an alkylene group of 2 - 4 carbon atoms; R.sub.1 is a hydrogen atom or a C.sub.1-6 alkyl group; R.sub.2 is a hydrogen atom, a C.sub.1-6 alkyl, phenyl, tolyl or benzyl group or is linked to R.sub.1 so that NR.sub.1 R.sub.2 is a 5-, 6- or 7- membered saturated ring; R.sub.3.sup.' is an aryl or aralkyl group; R.sub.4 is a hydrogen atom or a C.sub.1-4 alkyl group; and R.sub.5 is a hydrogen atom or a C.sub.1-4 alkyl group; possess mood-modifying and anorexia inducing activity.
U.S. application Ser. No. 599694 did not state that corresponding chromenes might possess useful mood-modifying or anorexia inducing activity. However it has now been discovered that certain specific chromenes and tetralenes do possess mood-modifying activity not possessed by the whole class.